Hydrological extremes and migration: How does water influence migratory movements?

“Today environmental problems play a role in migration. Some migrations occur when there is either too much water, as in rising seas, tsunamis and floods, or not enough water. In these countries people depend on the environment for their livelihoods.”

Wennersten, John R. and Denise Robbins. Rising Tides: Climate Refugees in the 21st Century.

Since 1993, the international community has commemorated World Water Day on March 22 of each year to highlight the need to responsibly preserve and manage this resource. In 2023, the selected theme is “accelerating change”, which intends to make visible the delay in the commitment to SDG 6 and the need to accelerate change to achieve the goals set for 2030.

From a migration perspective, it is necessary to understand and address the relationship between water and human mobility. This relationship is particularly evident in situations of hydrological extremes; both when water is lacking and when excess water affects living conditions. In the Americas there are cases of both scenarios and it is worth remembering them when studying the relationship between water and migration.

• Droughts and migration: When lack of water affects the livelihoods and subsistence of rural populations

Scientific evidence on climate change predicts more intense drought events in certain regions of the Americas in the future, such as in the small island states of the Caribbean, areas of Central and South America (IPCC, 2018). These phenomena are evident today in different countries. The Dry Corridor of Central America, which brings together areas of Guatemala, El Salvador, Honduras, and Nicaragua, and even Costa Rica and Panama, has had recurring drought events with significant effects on production and agricultural yields although with different problems according to geographical areas. In Chile, the state of mega-drought in the central zone since 2010 has required the declaration of agricultural emergency zones to alleviate the lack of water.

Recurrent drought events affect the livelihoods of local populations, particularly in rural and agricultural contexts, through decreased yields, reduced need for labor and even direct impacts on food security when income decreases, or production does not allow needs to be subsidized. These factors can provoke migratory movements when families seek better survival options in the face of drought, and there is scientific evidence that suggests households migrate locally or internally in response to drought (IPCC, 2019).

However, to attribute the cause of migration to drought phenomena is complicated for several reasons. On the one hand, drought can reduce the incomes of the poorest households, which no longer have the means to migrate, especially with regard to international migration (IPCC, 2019). Furthermore, droughts are often a gradual and progressive phenomenon, in which households often try various adaptation strategies before leaving their communities. The dependence on rainwater - due to the type of crop and the limitations of the irrigation systems - increases vulnerabilities in the event of a drought. The dependence on agriculture fed by rainwater is more than 30% in countries such as Guatemala, Honduras and Nicaragua, where the yield of corn and beans change greatly due to climatic variability.

The narrative around the motivating factors of the 2018 large migrant movements reflects some of these debates. While the press identified drought and climate change as a factor in explaining these movements, climate factors never appeared among the first motivations in surveys of migrants. Although there is some overlap, the areas most affected by drought in Honduras, for example, do not correspond to the first areas of origin of migrants according to IOM surveys. However, the high percentage of migrants who worked in the primary sector before their departure and the actual incidence of drought in various areas did allow for a glimpse of the impact of drought on the loss of opportunities at the local level.

• Floods, tsunamis, hurricanes: Hydrometeorological disasters as a source of displacement

In reports from the Internal Displacement Monitoring Center (IDMC), the category of climate-related disasters includes storms, cyclones, typhoons and hurricanes, floods, drought, fires and others. These disasters caused 16.1 million new displacements in 2018, a higher number than displacements caused by conflict and violence (10.8 million) and by geophysical phenomena (1.1 million).

As recent examples from Irma, Maria (2017) and Dorian (2019) show, Caribbean countries are particularly exposed to extreme hydrometeorological phenomena in which strong winds and rains destroy communities and cause mass displacement. However, the Caribbean countries are not the only ones in the region suffering from flood displacement. In recent months there have been heavy floods in Mexico, Brazil and Colombia due to excess rain and the limited capacity of watercourses to channel the torrent.

Displacement due to floods can be temporary or more permanent depending on the situation of the communities before, during and after the disaster. Certain families can return to their communities of origin after the event, when the waters return to their channel. This type of mobility has been evidenced, for example, in communities in Brazil and Argentina, in which recurrent floods promote the seasonal mobility of families outside the danger zone during certain months of the year.

Vulnerability to floods also causes more permanent migratory movements, both for individuals and communities. Hurricane Mitch, for example, caused the departure of Honduran populations in 1998. Some of these migrants accessed the Temporary Protection Status (TPS) in the United States, a status that remains in force for Honduras after a judicial decision that curbed the will of the administration of shut down the protection system.

Planned relocations of populations often respond to the desire to reduce risks related to hydrometeorological phenomena and also represent a form of human mobility. These processes have taken place in many countries in the region. In Nicaragua, for example, several communities around Lake Managua have been relocated to limit the damage caused by regular flooding and improve the living conditions of the populations. Sea level rise is also leading multiple countries in the region, such as Colombia, Panama or Guyana, to consider the potential need to move coastal communities to areas that will not be flooded in the relatively near future (IPCC, 2019).

References

IPCC. 2018. Global warming of 1.5°C. An IPCC Special Report on the impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty [V. Masson-Delmotte, P. Zhai, H. O. Pörtner, D. Roberts, J. Skea, P.R. Shukla, A. Pirani, W. Moufouma-Okia, C. Péan, R. Pidcock, S. Connors, J. B. R. Matthews, Y. Chen, X. Zhou, M. I. Gomis, E. Lonnoy, T. Maycock, M. Tignor, T. Waterfield (eds.)]. In Press.

IPCC. 2019. Climate Change and Land: an IPCC special report on climate change, desertification, land degradation, sustainable land management, food security, and greenhouse gas fluxes in terrestrial ecosystems [P.R. Shukla, J. Skea, E. Calvo Buendia, V. Masson-Delmotte, H.-O. Pörtner, D. C. Roberts, P. Zhai, R. Slade, S. Connors, R. van Diemen, M. Ferrat, E. Haughey, S. Luz, S. Neogi, M. Pathak, J. Petzold, J. Portugal Pereira, P. Vyas, E. Huntley, K. Kissick, M. Belkacemi, J. Malley, (eds.)]. In press.

IPCC. 2019. IPCC Special Report on the Ocean and Cryosphere in a Changing Climate [H.-O. Pörtner, D.C. Roberts, V. Masson-Delmotte, P. Zhai, M. Tignor, E. Poloczanska, K. Mintenbeck, A. Alegría, M. Nicolai, A. Okem, J. Petzold, B. Rama, N.M. Weyer (eds.)]. In press.

About the author

Pablo Escribano is the Migration, Environment and Climate Change Regional Thematic Specialist for the countries of the Americas and the Caribbean at the IOM Regional Office in San Jose, Costa Rica. Pablo Escribano has a master's degree in political science and history from the Institut d'Etudes Politiques de Paris (Sciences Po) and a bachelor's degree in political science from the same university.